Oil burner



y 1937- J, H. MCILVAINE El AL 2,080,289

OIL BURNER Filed June 12, 1935 3 Sheets-Sheet 1 y 1937- J. MCILVAINE El AL 2,080,289

OIL BURNER Filed June 12, 1935 3 Sheets-Sheet 2 May 11, 1937. J. H. MclLVAlNE ET AL OIL BURNER 3 Sheets-Sheet 5 Filed June 12, 1935 fill valve housings for support thereof.

Patented May 11, 1937 UNITED STATES PATENT OFFICE OIL BURNER Application June 12, 1935, Serial No. 26,112

9 Claims.

This invention relates to liquid fuel or hydrocarbon burners, commonly known as oil burners, suitable for industrial or domestic heating, and is concerned with improvements on the burner disclosed in the copending applications of John H. McIlvaine, Serial Nos. 651,083, filed January 11, 1933, and 748,698, filed October 17, 1934.

One of the principal objects of our invention is to provide, preferably in a single casting, a fan housing, float valve housing, and trip bucket housing, all in a compact and symmetrical arrangement with a view to economy of construction and at the same time obtaining a neater and more pleasing appearance. The motor for driving the fan is, in accordance with our invention, carriedon a bracket, one portion of which forms a closure plate for an opening in the side wall of the fan housing through which the fan rotor is entered or removed.

A feature of this one-piece casting is the provision of means whereby the trip bucket housing is utilized as the supporting base, there being a vertical connecting web joining the top of said housing with the bottoms of the fan and float Another feature is the provision of a tubular portion integral with said connecting web and so dis posed with respect to the float valve and trip bucket to serve as an enclosure and guide for the chain of the trip bucket in addition to serving as a conduit for overflow oil from the overflow pipe of the float valve to conduct such oil to the trip bucket. Still another feature is the provision of a trap on one side of the trip bucket housing communicating on the one hand with a conduit for conducting unconsumed oil from the firepot and having a discharge neck or spout extending therefrom into the trip bucket housing over the trip bucket therein so as to discharge such oil into said bucket.

The invention is illustrated in the accompanying drawings, in which Figure 1 is a side view of an oil burner embody ing our invention, showing it applied to a domestic heater or furnace;

Fig. 2 is a plan view of the burner with intermediate portions of the air conduit and oil re turn pipe broken away;

Fig. 3 is an end view of the burner;

Fig. 4 is a view looking at the other side of the burner;

Fig. 5 is a slightly enlarged vertical crosssection on the broken line 5--5 of Fig. 1;

Fig. 6 is a vertical longitudinal section on the broken line 66 of Fig. 5;

Fig. 7 is a face view of the rotary shutter plate removed from the fan housing;

Fig. 8 is a face view of the companion stator portion therefor on the fan housing, and

Fig. 9 is a sectional detail of said stator portion on the line 9-9 of Fig. 5.

The same reference numerals are applied to corresponding parts throughout the views.

In describing the burner of our invention, the liquid fuel will be referred to as oil and the oil circuit will be traced first. The oil is stored in a basement storage tank or under-ground storage tank outside. Where an under-ground tank is used, an automatic transfer pump is provided to pump the oil into the basement. The oil flows by gravity through the pipe 9 to the filter ill which removes any dirt and foreign matter so that only clean oil is delivered to the, burner. From the filter, the oil enters the bottom of the float valve 1 l, the purpose of which is to maintain a constant level of fuel, indicated by the line .r-y in Figs. 4 and 6, so as to insure an even pressure of fuel and an even flame free from pulsa tions or surges. The oil flows from the fioat valve by gravity through pipe connection l2 to a solenoid valve it, which permits an unrestricted flow of oil therethrough so long as the current for the electric motor 2! is not interrupted, the solenoid valve being kept open by the energization of its coil by the current for operating the motor. If the current is interrupted, a main valve in the solenoid valve l3 closes, and the oil is by-passed through a secondary valve therein that is adjusted to reduce the flow to about one-third the maximum capacity of the burner, whereby to maintain a reduced flame using natural draft, and sufficient to keep the house warm until normal operation will be resumed. The oil passes from the solenoid valve !3 into a control valve It that is preferably constructed as disclosed in the copending application of Peter I. Hellman, Serial No. 751,865, filed November '7, 1934. The valve I4 is adjusted to regulate the oil feed according to the heat demand. From this valve, the oil flows by gravity through the connection P5 to the pipe l6 which extends lengthwise inside the air conduit I1, and discharges the oil at l8 onto the tray 19 in the firepot 29. The firepot construction and method of oil burning employed therein forms part of the subject matter of a copending application of John H. Mcllvaine and Peter I. Hollman, Serial No. 74,952, filed April 1'7, 1936.

It is clear from this description that the present burner has simple gravity feed regulated in accordance with heat demand by the valve M, and controlled by the solenoid valve l3 to change from a normal oil feed to a restricted feed to provide a low carry over flame when the current for the motor is interrupted, as, for example, by reason of a temporary shut-down of the electric service for the home.

The air for mixture with the vaporized fuel and to support combustion is supplied by a centrifugal fan 22 in the housing 23. The latter has a tangential discharge neck 24 communicating at its flanged down-turned end 25 with the flanged end 26 of the air conduit I! to deliver air to the firepot 20, where the mixing of air and oil vapors and combustion of the mixture occurs. Bolts 21 fasten the neck of the fan housing onto the outer end of the air conduit at 2526. The jog in the air connection between the fan housing 23 and firepot 20 permits extension of the oil feed pipe l6 through a hole in the rear end of the conduit i! so that it is convenient to run a ramrod through the pipe, for cleaning purposes, upon removal of the cap 23. The pipe can, if necessary, be removed by loosening the union nut 29. It is clear in Fig. 5 that the fuel feed pipe l6 and its cap 28 are. properly disposed to one side of the web 41 to permit entering a cleaning rod into the pipe upon removal of the cap 28, or to remove the pipe rearwardly from the air conduit. The fan rotor 22 is suitably fixed on the armature shaft 30 of the motor 2!. The amount of air delivered by the fan is regulated by the turning of a shutter plate or rotor 3| relative to an apertured stator 32 on the side of the fan housing 23. The air shutter 3 l32 is constructed generally in accordance with Mc- Ilvaine Patent 1,797,293. The stator 32 has two diametrically opposed segmental openings 33-34 with which diametrically opposed quadrants of openings 3535 are arranged to register. The openings have closure plates 3'! adjusted so that only the proper amount of air is allowed to enter at each one of a series of adjusted positions of the plate 3|, the plate being turned one step at a time, and adjustments of the appropriate closure plates being made at each step so as to secure the correct amount of air delivery for each position, as fully set forth in the last-mentioned patent. A link 38 provides an operating connection between the shutter plate 3! and the rotatable crank arm 39 of the regulator 46, that is, where automatic control is desired; in some installations a remote control unit is provided having connection with the shutter plate for direct manual adjustment thereof. In the automatic control, the room thermostat located conveniently upstairs causes the regulator 40 to operate so as to adjust the size of the flame and constantly balance the heat loss of the building, and thus maintain an even temperature. Another link M provides an operating connection between the plate 3! and a lever 42 adjustably connected with a quadrant 43 fixed to the rotatable stem of the control valve l4, so that the control valve will be opened wider and wider at each step in the Wider and wider opening of the air shutter, whereby the correct proportioning of oil and air for each flame adjustment is assured, assuming that the closure plates 3! have been properly adjusted at the time of installation.

In accordance with the present invention, the fan housing 23 not only has the neck 24 cast integral therewith, but also a housing 44 for the float valve II and another housing 45 for a trip bucket 46, the housing 45 being joined to the bottoms of the housings 23 and 44 by a web 41, as best appears in Fig. 1. This close coupling of the housings in a single casting is made feasible by the fact that the firepot 2B is an open top type and set down low in the furnace at or below the grate level, the air conduit and oil feed pipe being extended to the firepot through the ash door opening, as shown, instead of the fire door opening. The jog or ofiset at 2523 provided in the air conduit permits extension of the conduit through the ash door opening, besides offering the advantage mentioned before with regard to cleaning out the oil feed pipe. The casting in one piece of the housings 23, 44, and 45 lowers the cost of the unit considerably and greatly improves its appearance. The trip bucket housing 45 forms the supporting base for the unit, brackets 48 being provided on opposite sides thereof, resting on the floor, having vertical slots 59 therein in which bolts 58 projecting from the housing are adjustable. Nuts 5! threaded on the bolts are tightened to clamp the housing in adjusted position and thus determine the elevation of the unit. A single post 52 serves to support the firepot 20, a set screw 53 being tightened to hold the firepot at the desired elevation.

In the event the flame in the firepot is accidentally extinguished, oil overflows the tray l9 and runs out of the bottom of the firepot 20 through a return pipe 54 into the trip bucket 45. A trap 55 fastened onto the side of the housing 45, as at 5t, is interposed between the rear end of the return pipe 54 and the trip bucket 46, and always contains enough oil to prevent escape of any smoke or vapors from the firepot through the pipe 5 1. The trap 55 is preferably a one-piece casting, for the sake of economy, and has a laterally extending discharge spout 5'! which projects through an opening 58 in the side wall of the housing 45 to a point directly over the bucket 46, so as to discharge into the bucket any oil coming from the firepot through the pipe 54. The bucket is shown as suspended on a chain 58 from the trip lever 59 pivoted at 60 on top of the float valve H. The lever 59 forms a part of a trip mechanism similar to that disclosed in McIlvaine Patent 1,692,046, the same embodying a drop weight also pivoted at and normally disposed at one side of dead-center in a raised cocked position, but arranged when the lever is.

moved downwardly by the loading of .the trip bucket to be moved over dead-center so as to drop onto the lever 59 with a hammer-like blow. lever 59 is disposed over the projecting end 62 of the needle valve or other equivalent element in the float chamber, and serves to depress the same and shut off communication between the oil supply pipe 9 and the float chamber, so that no further oil will be delivered. The trip bucket is also arranged to catch oil draining from the float valve l I through an overflow pipe 63. The latter communicates with the float chamber at a point just below the cover thereof and well above the normal level of oil indicated by the line a:-y. Thus, if the oil level rises in the float valve, due to a failure of the float mechanism to close the needle valve, overflow oil is drained through the pipe 53 into the trip bucket 46 to cause the trip mechanism to close the needle valve in the manner stated before. In accordance with the present invention, the connecting web t? between the trip bucket housing 45 and the other housings 23 and M is formed to provide a vertical tubular portion 64, as indicated in Figs. 5 and 6, through The.

which the chain 58, above mentioned, can be extended as shown, and thus protect it from accidentally being brushed against and causing the operation of the trip mechanism. The chain is furthermore kept out of sight to such an extent that children or others are not apt to tamper with it and throw the burner out of operation. The enclosure of the trip mechanism and trip bucket is, of course, provided for a similar reason. The portion 54 also has the free end of the overflow pipe 63 extended into it so as to be sure of the proper relationship to the trip bucket. A T fitting 63a connects the pipe 63 to the float valve H, and also provides communication between a vent pipe 63b and the float valve, above the oil level ry. This latter connection is to vent air from the oil line ahead of the valve l4 so that no air bubbles will occur in the oil fed through pipe IE to the firepot and disturb the evenness or continuity of the stream of oil discharged into the firepot. The front of the housing 45 is open to afford access to the trip bucket 46, but a door 65 is provided, hinged at its upper end, as at 66, to hang normally in closed position to keep the trip bucket 46 concealed until such time as the same has to be emptied.

Referring now, in particular, to Figs. 5 and '7 to 9, attention is called to the fact that one side wall of the fan housing 23 has a large circular opening 6'! provided therein, large enough to permit entry of the fan rotor 22. In accordance with our invention, the bracket 68 on which the motor 2| for driving the fan is mounted, is formed integral with a closure plate 69 closing the opening 61 and suitably secured, as indicated at 10, to the fan housing at circumferentially spaced points around the opening. The advantages of this construction from the standpoints of simplicity and economy, as well as neat appearance, must be selfevident. The opposite side wall of the housing 23 is cast to form the stator 32 of the air shutter integral with the housing to make for further simplicity and economy of construction, and enhance the appearance by eliminating the necessity for exposed screws which would otherwise be required if a separate stator plate had to be fastened to the housing. The stator 32, as must be evident from Figs. 5, 8 and 9, comprises an outer wall a in which the segmental openings 33 and 34 are provided, an inner wall 2) parallel to the outer wall a having a circular opening H registering with the inside of the fan rotor 22, and a peripheral wall 0 joining the outer and inner walls a and b, the wall 0 being of the same diameter as the openings 33 and 34 but being reduced to the diameter of the openings ll between the openings 33 and 34, as shown in Fig. 9. The wall 0 prevents return flow of any air from the housing 23 discharged from the rotor 22 and serves to conduct air admitted through the openings 33 and 34 to the opening H from which point the rotor 22 derives its air supply.

It is believed the foregoing description conveys a good understanding of the objects and advantages of our invention. The appended claims have been drawn with a view to covering all legitimate modifications and adaptations.

We claim:

1. In combination with a liquid fuel burner and an apparatus for feeding fuel and air under pressure thereto, said apparatus including a fan housing and an air conduit extending from said housing to said burner, the rear end of said conduit being offset with relation to the rest of said conduit, and a fuel feed pipe extending through the air conduit to the burner and projecting rearwardly from said conduit at the offset and arranged for removal endwise from said conduit rearwardly; a supporting structure for said apparatus comprising a base housing and an upward extension from said housing connecting the same rigidly to the fan housing, said extension being laterally offset in relation to the fuel feed pipe, whereby to permit movement of said pipe endwise rearwardly past said extension, a fuel receptacle enclosed in the base housing, a float controlled fuel valve and a trip mechanism therefor operative to close said valve to shut ofi fuel feed, both being disposed above the base housing, means extending into said base housing and connecting said receptacle with said trip mechanism, and means for conducting overflow and unconsumed fuel from said valve and burner, respectively, into said receptacle.

2. In combination with a liquid fuel burner and an apparatus for feeding fuel and air under pres sure thereto, said apparatus including a fan housing and an air conduit extending from said housing to said burner, the rear end of said conduit being ofiset with relation to the rest of said conduit, and a fuel feed pipe extending through the air conduit to the burner and projecting rearwardly from said conduit at the offset and having a removable closure on said projecting end; a supporting structure for said apparatus com prising a base housing and an upward extension from said housing connecting the same rigidly to the fan housing, said extension being laterally offset in relation to the fuel feed pipe, whereby to permit movement of a cleaning rod past said extension into and out of the oil feed pipe upon removal of its closure, a fuel receptacle enclosed in the base housing, a fuel valve and a trip mechanism therefor operative to close said valve to shut off fuel feed, both being disposed above the base housing, means extending into said base housing and connecting said receptacle with said trip mechanism, and means for conducting unconsurned fuel from said burner into said receptacle.

3. In an apparatus for feeding fuel and air to a liquid fuel burner, a fan housing, a base housing therebelow in spaced relation thereto and rigidly connected therewith by a vertical wall, the fan housing having a tangential discharge neck terminating in a downturned end portion, a horizontal air conduit for delivering air to the liquid fuel burner disposed in a horizontal plane between the base housing and fan housing but in laterally offset relation to saidwall, said conduit having the rear end thereof communicating with the downturned end of the aforesaid discharge neck, a fuel feed pipe extending lengthwise through said air conduit for delivering liquid fuel to said burner, said pipe extending from the rear end of said conduit, a fuel valve for supplying fuel to said feed pipe, and a trip mechanism operative to close said valve to shut off fuel feed, said trip mechanism including a trip bucket enclosed in the base housing.

l. In an apparatus for feeding fuel and air to a liquid fuel burner, a fan housing having a tangential discharge neck terminating in a downturned end portion, a horizontal air conduit for delivering air to the burner and having the rear end communicating with the downturned end of said neck, a supporting structure comprising a pair of laterally spaced supports, a housing adjustable vertically on said spaced supports, means providing a rigid close-coupled connection between the second housing and the fan housing to support the latter for adjustment with the second housing as a unitary assembly, the two housings being closely vertically spaced, a fuel feed pipe extending lengthwise through said air conduit for delivering liqiL'd fuel to the burner, said pipe extending from the rear end of said conduit in the same horizontal plane with the last-named space, whereby the pipe is arranged to be moved through said space between the housings into and out of the air conduit, a fuel valve for supplying fuel to said pipe, a trip mechanism operative to close said valve to shut off fuel feed and including a trip bucket enclosed in the second housing, and means for conducting unconsumed fuel from the burner to said bucket.

5. In an apparatus for feeding fuel and air to a liquid fuel burner, a fan housing having a tangential discharge neck terminating in a downturned end portion, a horizontal air conduit for delivering air to the burner and having the rear end communicating with the downturned end of said neck, a supporting structure comprising a pair of laterally spaced supports, a housing adjustable vertically on said spaced supports, means providing a rigid close-coupled connection between the second housing and the fan housing to support the latter for adjustment with the second housing as a unitary assembly, the two housings being closely vertically spaced, a fuel feed pipe extending lengthwise through said air conduit for delivering liquid fuel to the burner, said pipe extending from the rear end of said conduit in the same horizontal plane with the last-named space and having a removable closure on the projecting end accessible through said space between said housings, whereby to permit movement of a cleaning rod through said space into and out of the pipe upon re moval of said closure, a fuel valve for supplying fuel to said pipe, a trip mechanism operative to close said valve to shut off fuel feed and including a trip bucket enclosed in the second housing, and means for conducting unconsumed fuel from the burner to said bucket.

- 6. In an apparatus for feeding fuel and air to a liquid fuel burner, a fan housing having a tangential discharge neck terminating in a downturned end portion, a horizontal air conduit for delivering air to the burner and having the rear end communicating with the downturned end of said neck, a supporting structure comprising a base housing, means providing a rigid closecoupled connection between the base housing and the fan housing to support the latter, the two housings being closely vertically spaced, a fuel feed pipe extending lengthwise through said air conduit for delivering liquid fuel to the burner, said pipe extending from the rear end of said conduit in the same horizontal plane with the last-named space, whereby the pipe is arranged to be moved through said space between the housings into and out of the air conduit, a fuel valve for supplying fuel to said pipe, a trip mechanism operative to close said valve to shut off fuel feed and including a trip bucket enclosed in the second housing, and means for conducting unconsumed fuel from the burner to said bucket.

'7. In an apparatus for feeding fuel and air to a liquid fuel burner, a fan housing having a tangential discharge neck terminating in a downturned end portion, a horizontal air conduit for delivering air to the burner and having the rear end communicating with the downturned end of said neck, a supporting structure comprising a base housing, means providing a rigid close-coupled connection between the base housing and the fan housing to support the latter, the two housings being closely vertically spaced, a fuel feed pipe extending lengthwise through said air conduit for delivering liquid fuel to the burner, said pipe extending from the rear end of said conduit in the same horizontal plane with the last named space and having a removable closure on the projecting end accessible through said space between said housings, whereby to permit movement of a cleaning rod through said space into and out of the pipe upon removal of said closure, a fuel valve for supplying fuel to said pipe, a trip mechanism operative to close said valve to shut oif fuel feed and including a trip bucket enclosed in the second housing, and means for conducting unconsumed fuel from the burner to said bucket.

8. In an apparatus for feeding fuel and air to a liquid fuel burner, a fan housing communicating with the burner to deliver air thereto, a base housing below the fan housing in spaced relation thereto and rigidly connected therewith by a vertical wall, the fan housing being on one side of said wall, a tube extending upwardly from the top of the base housing on the other side of said wall, a fuel valve for supplying fuel to said burner, a trip mechanism operative to close said valve to shut off fuel feed, the trip mechanism being disposed over said tube, a trip bucket enclosed in the base housing and operatively connected with the trip mechanism by a flexible connection extending upwardly through said tube, means for conducting unconsumed fuel from the burner to said bucket, and housing means extending from the aforesaid vertical wall on the opposite side from the fan housing and enclosing said trip mechanism.

9. An apparatus as set forth in claim 8, wherein the fan housing has a tangential discharge neck terminating in a downturned end portion on the same side of the vertical wall with the fan housing, a horizontal air conduit for delivering air to the burner having the rear end thereof communicating with the downturned end of the aforesaid discharge neck also on the same side of the vertical wall with the fan housing, and a fuel feed pipe extending lengthwise through said air conduit for delivering liquid fuel to the burner, said pipe extending from the rear end of said conduit in laterally spaced relation to the vertical wall and in the space between the fan housing and base housing, for the purposes described.

JOHN H. McILVAINE. PETER I. HOLLMAN. 

